​​In winter, majestic bald eagles are perched on cottonwood trees or soar over the water. The reservoir eco-system attracts raptors species including golden eagle, red-tailed hawk, northern harrier and ferruginous hawk as well as waterfowl and shorebirds.

The bird list, available at the park office or entrance stations, provides information about the many species of migratory and resident birds observed here.

Visitors might see plains species of lark bunting, horned lark and meadowlark. A nesting colony of black-crowned night herons use wooded wetlands on the western side of the reservoir. Colonies of prairie dogs provide habitat for nesting and brood-rearing by burrowing owls, a threatened species in Colorado.